en_tn_condensed/isa/40/10.md

his strong arm rules for him

Here the word "arm" represents God's power. Alternate translation: "he rules with great power" (See: rc://en/ta/man/translate/figs-metonymy)

his reward is with him ... those he has rescued go before him

These two phrases mean basically the same thing. The ones he rescued are his "reward." Alternate translation: "he is bringing those he rescued with him as his reward" (See: rc://en/ta/man/translate/figs-parallelism)